In digital data communications, the transmission speed of the communications link from one node to another is one of the main factors in the bandwidth. To improve efficiency, systems using various bandwidths (at different transmission speeds) have been made available.
A number of carrier systems having different bandwidths are available from common carriers, such as AT&T. These systems include T1, T1C, T2 and other systems, each of which is associated with a specific data transmission rate. For example, the T1 system is associated with a 1.544 Mbps data rate, also referred to as the DS1 rate, and provides up to 24 combined data and PCM voice channels. The T2 carrier system is associated with a 6.132 Mbps data rate (DS2), and provides 96 channels. The FT3 system is an optical fiber carrier system with a 44.736 Mbps (DS3), and provides 672 channels. A single channel voice grade line is referred to as a DS0 line.
A recent development in data communications has been systems in which different units of equipment associated with different bandwidths are linked in the same network. For example, DS0 equipment might be integrated with DS1 or DS3 equipment, with all equipment being managed by a single management system. Networks that manage or integrate equipment for different bandwidths are referred to as "multi-bandwidth systems".
Another recent development in data communications has involved new system management techniques for the benefit of multiple network subscribers. One new technique is the partitioning of bandwidths, in which the bandwidth service provider allocates the bandwidth in a network among different subscribers. Each subscriber's portion of the network is referred to as its "private virtual network".
Often in partitioned systems, the service provider manages a bandwidth pool. From this pool, each subscriber is allocated a certain permanent bandwidth, but if for some reason, that bandwidth is temporarily unavailable or insufficient, the subscriber's portion of the network may be reconfigured from a pool of unallocated bandwidth.
The more innovative partitioned bandwidth systems give each subscriber the ability to control the bandwidth assigned to it by the service provider. Typically, the subscriber has a computer terminal with access to a management system. One type of management system for partitioned networks, referred to as a "customer controlled configuration" system, permits the subscriber to change the bandwidth available to it. The result is an economic savings in that the customer need not pay for more bandwidth than is needed at a given time. A problem with such existing systems, however, is that at the central management level, changes in the physical elements of each customer's virtual network make maintaining records of each customer's network difficult.
A characteristic of today's management systems for partitioned, multi-bandwidth, networks is the need to tie equipment together using physical device identifiers. In other words, the management system defines connections through different bandwidths in terms of specific physical components. However, from the service provider's point of view, record keeping and restoration is complicated. From a subscriber's point of view, the need for a physical representation of the network requires that network configurations be performed by someone specially knowledgeable about the physical network components.
The increasing use of partitioned, multi-bandwidth, networks calls for improved management methods. Ideally, a partitioned multi-bandwidth system should permit each subscriber to directly implement bandwidth requests, without the need to make requests at a central administrative level. Also, the system must not be overly complicated from the subscriber's point of view. A need has arisen for management systems which provide the ability to reconfigure the physical network resources managed by the system without impacting the user's perspective of the network, or in other words, the ability to provide transparency. Further, a need has arisen for such a management system which selectively enables such transparency at any network resource or user-subscriber level in the network hierarchy.